The present invention relates to novel peptides which are maturation products of polypeptides secreted by the submaxillary gland of the rat and analogues of these peptides.
Many polypeptides having defined biological properties are synthesized in large quantities in the submaxillary gland (SMG) of rodents, and in particular in the SMG of the mouse. These proteins, comprising the nerve growth factor (NGF), the epidermal growth factor (EGF) and renin, have a certain number of properties in common. They are all synthesized in the same type of cell, namely the cells of the convoluted tubules GCT (granular convoluted tubular), in response to various hormonal stimuli, in particular to androgens. Furthermore, it is possible to observe the presence of these secretory proteins in the saliva of the mouse, and they are synthesized in the form of precursors which become active after maturation processes which may involve proteases of the kallikrein type. Some of these proteases of the kallikrein type are also synthesized in the SMG under the control of androgens.